But Djokovic, a 34-year-old from Serbia, couldn't get to 28-0. He simply was far from his best on this particular day.
He made mistakes, 38 unforced errors in all. He wasn't able to convert a break chance until it was too little, too late. He showed frustration, too, destroying his racket by pounding it three times against the court after one point, drawing boos from the Arthur Ashe Stadium crowd and a code violation from the chair umpire.
A lot of Djokovic's issues had to do with the No. 2-ranked Medvedev, who used his 6-foot-6 (1.98-meter) frame to chase down everything and respond with seemingly effortless groundstrokes — much the way Djokovic wears down foes — and delivered pinpoint serving.
Djokovic reached his record-equaling 31st Grand Slam final with six victories on the hard courts of Flushing Meadows. But he could not quite get the last one he needed.
He remains tied with Roger Federer and Rafael Nadal with 20 major titles.
And the last man to sweep a season's singles trophies at the Slams remains Rod Laver, who did it twice — in 1962 and 1969 — and was in the stands Sunday. The last woman to accomplish the feat was Steffi Graf in 1988.
Instead, Djokovic joins Jack Crawford in 1933 and Lew Hoad in 1956 as men who won a year's first trio of Grand Slam tournaments and made it all the way to the U.S. Open final before losing.